Having got my several 'send only' systems configured successfully (thank you all for your help doing this) I now have another fairly minor problem.
Errors from all of these systems are (mostly) sent by root, typically they will be cron or anacron processes. As these are just systems on my LAN they don't each have their own 'valid on the internet' hostname. Thus the error messages come from r...@zbmc.eu whichever system has sent it. While I can look through the E-Mail header to see where the message has come from it would be good if I could somehow configure things so that the headers I normally see (From:, To: and Subject:) include something that indicates where the message is from. So, is there something I can configure in postfix to always add some text of some sort (the hostname is the obvious thing) to one of From:, To: or Subject: ? -- Chris Green
